CUT THE STRIPS OF RIBS between the bones into riblets. Stir-fry the spareribs in a wok over high heat to brown them in their own fat (about 4 minutes). (You may want to start them off with a tablespoon of peanut oil.) Drain off the fat and add the sauce ingredients except the broth. Mix them well. Add the broth and reduce the heat. Let the ribs simmer 60 minutes. Remove the ribs to a serving plate and garnish them with the scallion tops. (The liquid in the wok can be skimmed of fat and thickened with cornstarch to make a sauce, if you like.) Serves 4 to 6 as a main course.